Derivatives (Fair Value Hedges) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	$ 138	$ (395)	$ 327	$ (675)
Net Derivatives Gains (Losses) Recognized for Hedged Items	(134)	403	(310)	675
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	4	8	17	0
Interest rate swaps [Member] | Fixed maturity securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(3)	30	(2)	38
Net Derivatives Gains (Losses) Recognized for Hedged Items	2	(30)	3	(38)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	(1)	0	1	0
Interest rate swaps [Member] | Policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	137	(383)	346	(536)
Net Derivatives Gains (Losses) Recognized for Hedged Items	(131)	381	(335)	533
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	6	(2)	11	(3)
Foreign currency swaps [Member] | Foreign-denominated fixed maturity securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(3)	13	(7)	17
Net Derivatives Gains (Losses) Recognized for Hedged Items	3	(11)	7	(16)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	0	2	0	1
Foreign currency swaps [Member] | Foreign-denominated policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	1	(55)	(26)	(194)
Net Derivatives Gains (Losses) Recognized for Hedged Items	(3)	63	29	196
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	(2)	8	3	2
Foreign currency forwards [Member] | Foreign-denominated fixed maturity securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	6	0	16	0
Net Derivatives Gains (Losses) Recognized for Hedged Items	(5)	0	(14)	0
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	$ 1	$ 0	$ 2	$ 0